JP4643515B2 - Fuel oil pump unit with float valve - Google Patents

Description

  The present invention relates to a fuel oil pump unit including a float valve.

For example, in a gas station such as a gas station, fuel oil is supplied from an underground tank to a vehicle or the like through a measuring unit using a pump unit built in the measuring unit.
Conventionally, a float valve used in the pump unit has been proposed (see Patent Documents 1 and 2).
JP-A-9-329271 (abstract) JP-A-11-257527 (abstract)

  By the way, as is well known, the fuel oil may be in a state where gas such as gas or air vaporized in the transport process is mixed as bubbles. Therefore, at the time of the refueling, the fuel oil is separated into a gas liquid and a liquid containing a gas by using a separation device. The gas liquid is introduced into a separation chamber and stored, whereby the gas liquid is separated into a liquid and a gas. The separated liquid is again sucked into the suction side of the pump. On the other hand, the separated gas is discharged into the atmosphere through an air opening (air vent).

  The separation chamber is provided with a first float valve below the separation chamber, and the liquid level in the separation chamber is kept substantially constant. However, if the liquid level in the separation chamber suddenly rises for some reason, fuel oil may be released from the air vent. When the fuel oil is discharged out of the pump unit, the ground of the filling station and the clothes of the workers become dirty and need to be cleaned.

  As a factor that causes the liquid level in the separation chamber to rise, for example, when the pump is stopped, fuel oil upstream of the pump may flow backward due to a temperature rise or oil drop and flow into the separation chamber. In general, a plurality of weighing machines are connected to the underground tank, so the pressure in underground pipes fluctuates drastically due to starting and stopping of pump units of other weighing machines, opening and closing of valves, and so-called water hammer. As a result, the liquid level in the separation chamber of the pump unit may rise.

Therefore, it is conceivable to provide a second float valve provided with a valve body that opens the air vent by self-sealing (lip) in the air vent to prevent the release of fuel oil from the air vent.
In Patent Documents 1 and 2, the second float valve is not provided.

  When the liquid level in the separation chamber rises for the reasons described above, the float of the second float valve rises in accordance with the rise of the liquid level, and the air vent is closed by the valve body of the second float valve. This prevents the fuel oil from being released from the air vent.

When the pump is operated in such a state, the fuel oil in the separation chamber is again sucked into the pump, and accordingly, the liquid level in the separation chamber is lowered and the pressure in the separation chamber is lowered.
However, when a gas-liquid mixed with a large amount of gas from the separation device flows into the separation chamber at this time, the pressure in the separation chamber that has risen above the atmospheric pressure does not decrease despite the liquid level being lowered, One pressure acts on the valve body having a self-sealing function, and there is a risk that the air vent remains closed.

  In addition, the miniaturization of the float used for the float valve greatly affects the miniaturization of the pump unit, so it is preferable to make it as small as possible. However, while the float valve moves the valve body by its own weight when the valve is opened, the weight of the float becomes smaller as the float becomes smaller, and the certainty of opening the valve by the dead weight of the float becomes even more difficult.

  Therefore, an object of the present invention is to provide a fuel oil pump unit including a float valve that can be downsized and can be reliably opened.

  In order to achieve the above object, a fuel oil pump unit according to the present invention comprises a separation device that swirls fuel oil discharged from a pump and separates it into a gas-liquid containing liquid and a liquid, and the separation device separates the fuel oil. A separation chamber for separating gas from the gas liquid and the pump are provided in a casing, and a fuel oil pump unit including a float valve provided in an air vent for communicating the separation chamber to the atmosphere, A suction cup-like lip that opens and closes the opening of the air vent; the lip contacts the valve seat when the valve is closed; and the lip opens and closes the air vent when the valve is open. A guide for movably guiding the valve body in a direction, and a first bypass hole that penetrates in the movement direction of the valve body and serves as a bypass when the lip in the valve closing state shifts to the valve opening state A rod having a cone portion that opens and closes the first bypass hole by moving up and down of a float provided in the separation chamber, and the air vent when the rod is retracted and the first bypass hole is opened. A float valve having a second bypass hole communicating with the separation chamber via the first bypass hole.

According to the present invention, when the lip in the valve-closed state shifts to the valve-opened state, even if the lip is in close contact with the valve seat, the first and second bypass holes are opened only by slightly lowering the float. The gas in the separation chamber is discharged from both bypass holes via the air vent, so that the pressure in the separation chamber is lowered and the lip is opened away from the valve seat.
Therefore, even when the liquid level in the separation chamber is lowered, the float valve can be reliably opened even when the pressure in the separation chamber is higher than the atmosphere. Further, even if a small float is used, the valve can be opened reliably.

In the present invention, when the rod closes the first bypass hole, the second bypass hole does not communicate with the first bypass hole, and the float valve communicates with the separation chamber. It is preferable to provide.
According to this aspect, when the valve closes the first bypass hole, the second bypass hole does not communicate with the first bypass hole, so that the valve can be reliably closed. On the other hand, since the second bypass hole communicates with the separation chamber, the first bypass hole is opened only when the rod is slightly retracted when the valve is opened, and the first and second bypass holes are interposed. Since the separation chamber and the air vent communicate with each other, the certainty of valve opening is increased.

In the present invention, the valve body is mounted, and further includes a tubular member guided by the guide and having a sliding hole through which the rod slides, and the second bypass hole is formed in the tubular member. There that have a float valve which is formed.
According to the present invention , since the second bypass hole is formed in the cylindrical member on which the rod slides, that is, the second bypass hole is formed in the cylindrical member different from the valve body that closes the valve seat. Therefore, when the first bypass hole is opened, the interior of the separation chamber immediately communicates with the atmosphere via the second bypass hole, so that the reliability of the valve closing can be further enhanced.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
Lubrication system:
First, an example of an oil supply system in which the present pump unit is used will be described.

As shown in FIG. 1, the oil supply system includes an underground tank 1, a pipe 2, a pump unit 3, a solenoid valve 4, a flow meter 5, a hose 6, and a nozzle 7.
When the nozzle 7 is inserted into the fueling port of the vehicle and fueling is started, the fuel oil F is pumped up from the underground tank 1 embedded in the fueling station via the pipe 2 by the pump unit 3 and discharged from the nozzle 7.

  As described above, since gas such as vaporized gas or air may be mixed in the fuel oil F, the gas mixed in the fuel oil F is removed by the pump unit 3, and the gas is removed. Only the liquid L passes through the solenoid valve 4, the flow meter 5, the hose 6, and the nozzle 7 and is supplied to the vehicle.

Pump unit 3:
Next, a schematic configuration of the pump unit 3 will be described.
Flow of fuel oil F and liquid L;
The pump unit 3 includes a rotary pump 20. When the pump 20 is activated, the fuel oil F supplied from the underground tank 1 through the pipe 2 to the pump unit 3 is sent from the inlet 10 of the pump unit 3 to the primary filter 11 (see FIG. 2A).

  The fuel oil F passes through the first check valve 12 from the primary filter 11, is sucked into the pump 20 from the suction side 20a of the pump 20, and is discharged from the discharge side 20b of the pump 20 to the separation device 31 (see FIG. 2B). ).

  The separation device 31 swirls the fuel oil F discharged from the discharge side 20b of the pump 20 and separates it into gas liquid FA and liquid L, which are liquids containing gas A (see FIG. 3A).

The separator 31 shown in FIG. 3A swirls the fuel oil F fed from the pump 20 in the separator 31 and collects the liquid L outward in the radius and the gas liquid FA in the radius due to the difference in centrifugal force. Gather toward you. Thereby, the liquid L and the gas liquid FA are separated (see, for example, Japanese Patent Publication No. 4-15399).
The liquid L separated by the swirling is sent to the secondary filter 32 in FIG. On the other hand, the gas liquid FA is led out to the gas liquid passage 35.

  The liquid L separated from the fuel oil F passes through the secondary filter 32, passes through the second check valve 33, and is supplied from the outlet 34 to the hose 6 through the electromagnetic valve 4 and the flow meter 5 (FIG. 3B). And FIG. 4).

Flow of gas-liquid FA;
The gas-liquid FA led out to the gas-liquid passage 35 is sent to the separation chamber 40. The separation chamber 40 stores the gas liquid FA. As a result, the liquid L accumulates in the lower liquid phase portion 40a and is separated into the liquid L in the liquid phase portion 40a and the gas A in the gas phase portion 40b (see FIG. 5B).
The liquid L separated by the separation chamber 40 is returned to the suction side 20a of the pump 20 through the first return passage 41 and the second return passage 42 (see FIGS. 4 and 2B).
On the other hand, the gas phase part 40b in the upper part of the separation chamber 40 communicates with the atmosphere via the air vent 45, and the gas A accumulated in the gas phase part 40b is discharged from the air vent 45 to the atmosphere (FIG. 2A). reference).

  Here, the gas-liquid passage 35 has an opening 35 a in the liquid phase portion 40 a of the liquid L accumulated in the separation chamber 40. Therefore, the gas-liquid FA discharged from the separation device 31 passes through the gas-liquid passage 35 and is guided to the liquid phase portion 40a of the separation chamber 40 while maintaining a state not communicating with the atmosphere.

First float valve V1;
A first float valve V <b> 1 is provided between the separation chamber 40 and the first return passage 41. The first float valve V1 includes a first float F1, and opens when the liquid L in the separation chamber 40 reaches a first predetermined amount. When the pump 20 is in operation, the liquid L passes through the first return passage 41. Then, it passes through the second return passage 42 and is sucked into the suction side 20a of the pump 20. The first float F1 functions to keep the liquid level of the liquid phase portion 40a so as to be always higher than the position of the opening 35a of the gas-liquid passage 35. That is, the first float valve V1 keeps the liquid level of the liquid phase portion 40a at or above a predetermined lower limit level.

Second float valve V2;
On the other hand, the air vent 45 is provided with a second float valve V2. The second float valve V2 includes a second float F2. When the liquid L in the separation chamber 40 exceeds a second predetermined amount, the second float F2 rises and closes the air vent 45. This prevents the liquid L in the separation chamber 40 from being blown out from the air vent 45. Therefore, the second float valve V2 has a function of preventing the liquid L from blowing down when the liquid level of the liquid phase part 40a exceeds a predetermined upper limit level.

Pump 20:
As shown in FIG. 2B, the pump 20, the separation device 31, and the separation chamber 40 are provided in the casing 50 of the pump unit 3.

  In FIG. 2B and FIG. 3A, the pump 20 includes an internal gear pump configured by an internal gear 25, a partition plate 26 and an external gear 27 accommodated in a pump chamber 56, for example. The rotation centers of the internal gear 25 and the external gear 27 are eccentric, and the internal gear 25 is rotated by the rotation of the external gear 27, so that the fuel oil F between the external gear 27 and the internal gear 25 is sucked into the suction side 20a. From the outlet toward the discharge side 20b. A pulley 24 for inputting a driving force is fixed to the end of the rotating shaft 23 of the external gear 27.

Next, characteristic parts of the pump unit will be described.
Second float valve V2:
As shown in FIG. 6, an air vent 45 and a second float valve V2 are provided on the chamber lid 50A that constitutes a part of the wall surface of the separation chamber 40 (see FIG. 2A).
The second float valve V2 includes a guide 48 provided integrally with the chamber lid 50A, an annular valve body 60 guided by the guide 48 via the cylindrical member 64 of FIG. 7, and an end of the float shaft 68. And a second float F2 (FIG. 6) fixed to the portion.

Valve body 60;
As shown in FIG. 7, a valve seat 46 is formed around the opening 47 on the valve body 60 side of the air vent 45. The valve body 60 includes a sucker-like lip 63 that opens and closes the opening 47, and is attached to the tubular member 64. The tubular member 64 is provided so as to be slidable in the opening / closing direction D within the guide 48, whereby the valve body 60 can be opened / closed in the opening / closing direction D.
In the valve open state shown in FIG. 7, the lip 63 is separated from the valve seat 46, and in the valve closed state shown in FIG. . When the pressure in the separation chamber 40 is higher than the atmospheric pressure, the lip 63 is pressed against the valve seat 46 in the closed state.

Rod 66;
As shown in FIG. 7, a sliding hole 65 is provided in the cylindrical member 64 along the opening / closing direction D, and a rod 66 is slidably provided in the sliding hole 65.

A rear end portion of the rod 66 on the float shaft 68 side is engaged with an end portion 68 a of the float shaft 68 via a first engagement pin 71. The end 68a is provided so as to be rotatable with respect to the bracket 48A around the rotation center O. A first long hole 72 is formed in the end 68a, and the first engagement pin 71 is set to be slidable in the first long hole.
When the float shaft 68 rotates about the rotation center O in accordance with the rising and lowering of the second float F2 (FIG. 6), the first engagement pin 71 engages with the first long hole 72 and the rod 66 is moved in the opening / closing direction D.

First bypass hole 61;
A substantially conical cone portion 67 is formed at the tip of the rod 66 on the lip 63 side.
On the other hand, a first bypass hole 61 is formed in the valve body 60 to communicate the surface of the lip 63 on the opening 47 side in the substantially central portion of the valve body 60 with the sliding hole 65. The first bypass hole 61 is formed smaller in diameter than the sliding hole 65, and when the rod 66 advances in the valve closing direction D <b> 1, the tip portion of the cone portion 67 of the rod 66 is fitted into the first bypass hole 61. In other words, when the rod 66 further advances, the cone portion 67 pushes the end portion of the first bypass hole 61 and advances the entire valve body 60 toward the valve seat 46.
As the valve body 60 moves forward, as shown in FIG. 8A, the lip 63 comes into close contact (sitting) with the valve seat 46, and the 2-float valve V2 is closed.

  Here, the rod 66 is provided with a second elongated hole 74 penetrating in the radial direction. The rod 66 is locked to the cylindrical member 64 via a second engagement pin 73 that passes through the second elongated hole 74. Therefore, when the rod 66 moves backward in the valve opening direction D2, the valve body 60 moves backward as shown in FIG.

Second bypass hole 62;
The tubular member 64 is formed with a second bypass hole 62 that opens from the circumferential surface of the tubular member 64 toward the cone portion 67 of the rod 66. That is, the second bypass hole 62 is formed in the radial direction of the cylindrical member 64.
On the other hand, as shown in FIG. 6, the guide 48 includes a plurality of protrusions 48a, and a part of the cylindrical member 64 is exposed in the separation chamber 40 from between the protrusions 48a. The second bypass hole 62 is provided between the projecting portions 48 a of the guide 48, and thus the separation chamber 40 and the sliding hole 65 communicate with each other through the second bypass hole 62.

In the valve closed state shown in FIG. 8A, the cone portion 67 of the rod 66 closes the first bypass hole 61 so that the second bypass hole 62 does not communicate with the first bypass hole 61.
On the other hand, when the rod 66 is slightly retracted in the valve opening direction D2 as shown in FIG. 8B during the transition from the valve closing state to the valve opening state, the lip 63 remains in close contact with the valve seat 46. The cone portion 67 that has blocked the first bypass hole 61 is separated from the first bypass hole 61. As a result, the separation chamber 40 communicates with the air vent 45 via the second bypass hole 62, the sliding hole 65, and the first bypass hole 61, and the gas A in the separation chamber 40 can be discharged from the air vent 45.

Next, the operation of the second float valve V2 will be described.
Transition from open to closed:
For some reason, when the level of the liquid L in the separation chamber 40 shown in FIG. 1 rises, the second float F2 rises, and the float shaft 68 shown in FIG. The rod 66 is advanced in the closing direction D1. As the rod 66 advances, the tip of the cone portion 67 is fitted into the first bypass hole 61. When the rod 66 further advances, the cone portion 67 pushes the opening of the first bypass hole 61, and the valve body 60 advances in the guide 48. As the valve body 60 advances, the lip 63 comes into close contact with the valve seat 46, whereby the second float valve V2 in FIG. 8A is closed.

Transition from closed to open:
When the pump is operated in such a state, the liquid L in the separation chamber 40 of FIG. 1 is sucked again by the pump, and accordingly, the liquid level of the liquid L in the separation chamber 40 is lowered and the gas phase portion 40b in the separation chamber 40 is reduced. The pressure drops.
However, at this time, as described above, when the gas-liquid FA mixed with a large amount of the gas A flows into the separation chamber 40 from the separation device 31, the separation chamber 40 is in spite of the liquid level of the liquid L being lowered. The internal pressure rises above the atmospheric pressure, and therefore the pressure in the gas phase part 40b in the separation chamber 40 may not decrease.

In such a case, since the liquid level of the liquid L in the separation chamber 40 is lowered, the float shaft 68 of FIG. 8A slightly rotates around the rotation center O due to the weight of the second float F2, and the lip As shown in FIG. 8B, the rod 66 is slightly retracted in the valve opening direction D2 while 63 remains in close contact with the valve seat 46.
Accordingly, the separation chamber 40 communicates with the air vent 45 via the second bypass hole 62, the sliding hole 65, and the first bypass hole 61, and the gas A in the separation chamber 40 is discharged from the air vent 45 to the atmosphere. As the gas A in the separation chamber 40 is exhausted, the pressure of the gas phase part 40b decreases, and the valve body 60 moves backward in the valve opening direction D2 due to the weight of the second float F2 (FIG. 1). By the retraction of the valve body 60, the lip 63 is separated from the valve seat 46, and the valve is opened as shown in FIG.

As described above, the liquid level of the liquid phase part 40a in the separation chamber 40 is lowered, but even if the internal pressure of the gas phase part 40b is not lowered, if the float shaft 68 is slightly lowered, the rod 66 is retracted. Since the first bypass hole 61 having a small pressure receiving area is opened by the weight of the float F2 and the internal pressure of the gas phase part 40b in the separation chamber 40 is reduced, the second float valve V2 can be opened.
Therefore, the second float valve V2 can be downsized, and even if the internal pressure of the gas phase portion 40b in the separation chamber 40 increases, the second float valve V2 can be reliably opened if the liquid level of the liquid phase portion 40a decreases. Can do.

  The present invention can be applied to a fuel oil pump unit having a float valve that opens and closes an air vent of a separation chamber.

It is a schematic block diagram which shows the oil supply system using the pump unit concerning one Example of this invention. It is a schematic sectional drawing which shows a pump unit. It is a schematic sectional drawing which shows a pump unit. 4A is a schematic front view of the pump unit, and FIG. 4B is a schematic cross-sectional view thereof. It is a schematic sectional drawing which shows a pump unit. It is a schematic perspective view which shows a float valve and an air vent. It is a schematic longitudinal cross-sectional view which shows the float valve of a valve opening state. FIG. 8A is a schematic cross-sectional view showing the float valve in the closed state, and FIG. 8B is a schematic cross-sectional view showing the float valve when shifting from the closed state to the open state.

Explanation of symbols

3: Pump unit 20: Pump 31: Separator 35: Gas-liquid passage (part of the discharge passage)
36: Communication passage (part of discharge passage)
40: separation chamber 50: casing 45: air vent 46: valve seat 48: guide 60: valve body 61: first bypass hole 62: second bypass hole 63: lip 64: cylindrical member 65: sliding hole 66: rod 67 : Cone part A: Gas D: Opening and closing direction F: Fuel oil F2: Second float FA: Gas liquid L: Liquid V2: Second float valve

Claims (2)

A separation device that swirls fuel oil discharged from a pump to separate the gas into liquid and liquid containing gas, a separation chamber that separates gas from the gas liquid separated by the separation device, and the pump Provided in the casing,
A fuel oil pump unit comprising a float valve provided in an air vent for communicating the separation chamber with the atmosphere,
An annular valve body that has a suction cup-like lip that opens and closes the opening of the air vent, the lip contacts the valve seat in a valve-closed state, and the lip separates from the valve seat in a valve-open state;
A guide for movably guiding the valve body in a direction to open and close the air vent;
A first bypass hole that penetrates in the moving direction of the valve body and becomes a bypass when the lip in the closed state shifts to the open state;
A rod having a cone portion that moves by vertically moving a float provided in the separation chamber to open and close the first bypass hole;
A second bypass hole that communicates the air vent with the separation chamber through the first bypass hole when the rod is retracted and the first bypass hole is opened ;
The valve body is mounted, and a cylindrical member guided by the guide and having a sliding hole through which the rod slides,
A fuel oil pump unit comprising a float valve in which the second bypass hole is formed in the cylindrical member.   2. The float valve according to claim 1, wherein when the rod closes the first bypass hole, the second bypass hole does not communicate with the first bypass hole and communicates with the separation chamber. Fuel oil pump unit provided.

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